In brief:
Yes

There are different types of crisis in sickle cell.

Untreated aplastic crises can cause death to to severe anemia. Untreated acute chest syndrome can cause death due to respiratory failure. Untreated splenic sequestration can cause death due to severe anemia. I would recommend not ignoring any crisis id sickle cell.

In brief:
Yes

There are different types of crisis in sickle cell.

Untreated aplastic crises can cause death to to severe anemia. Untreated acute chest syndrome can cause death due to respiratory failure. Untreated splenic sequestration can cause death due to severe anemia. I would recommend not ignoring any crisis id sickle cell.
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In brief:
Yes

This could be so bad as to cause a collapse of the cardiovascular system. It is common place for a crisis to cause strokes, bone necrosis, and severe lung damage, all potentially fatal.
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